It wasn't just the inhabitants of America's Gulf coast who were stunned by Hurricane Katrina a year ago. It was the whole American nation and the entire watching world. The death, destruction and displacement caused by the worst natural disaster in United States history swept away homes, wrecked the unique city of New Orleans and even laid siege to the American dream itself. The human catastrophe shocked even more brutally than the natural one did. That such things could happen in the world's richest and most self-confident society was hard to grasp then - as George Bush's own hapless response personified - and it remains even harder now. For if the original destruction could be described as an act of God, then the continuing failure to put it right can only be described as an act of humankind.

Yesterday, with midterm elections in the offing, Mr Bush spent rather more time in New Orleans than he managed to do a year ago during the disaster itself. But there is little sense in most parts of the afflicted Gulf coast, and in New Orleans itself in particular, that public officials from the president down have yet got a grip of the situation that confronts them. Huge questions and challenges remain. Some quarter of a million people (more than half the population of the metropolitan New Orleans area) remain displaced around the country. Only 41% of houses in the area have a gas service and only 60% have electricity. A mere 17% of the city's buses are in use. Only a third of New Orleans' public schools are in operation, along with less than a quarter of the city's childcare facilities. Waste collection systems remain vestigial in many areas, non-existent in some, and crime, especially violent crime, is rising. Unsurprisingly, in view of the scale of the destruction and the slow progress being made in fixing it, housing costs are rising rapidly (rents are up 39% since the hurricane struck).

All these things impact disproportionately on poor people rather than on the wealthy. And in New Orleans that largely means poor black people. The fabled areas of New Orleans that the tourists (and the president) visit are being rebuilt reasonably well. It is in the less glamorous outlying districts that the predicament is most serious, rehabilitation slowest and the need for progress most urgent. The failure to rebuild and restore New Orleans over the past 12 months, and in some cases the opportunist determination not to do so, simply cannot be understood except in a racial context. "I'm not saying they planned this as a way to empty New Orleans of poor, black people," a former resident of the stricken Lower Ninth ward told a New Yorker reporter earlier this month, "but it's sure going to work out that way."

In a devastated city and a region that are crying out for steady incremental progress and planning, improvements have been painfully slow and much has already stalled. Of the much touted $110bn of federal aid to the region, only $44bn has yet been handed over. Louisiana and New Orleans are bywords for corrupt government and failed politics, so not all of this can be laid at Mr Bush's door. Nevertheless, conspiracy theories abound. The suspicion that white property developers took advantage of the storm to destroy black neighbourhoods (it has happened in New Orleans before) is widespread. Professor Douglas Brinkley of Tulane University - author of The Great Deluge - believes the inaction is deliberate and politically motivated, its objective a smaller New Orleans with a large proportion of its former black citizenry (and voters) scattered to the north American winds, its ultimate goal to turn Louisiana, the last Democratic state in the Old South, into a Republican state like the rest of them. True or not, a full year on, Hurricane Katrina should continue to cause outrage about the rottenness and misery of the lives still lived in what Michael Harrington once famously called "the other America".